U.S. patent application number 15/768978 was filed with the patent office on 2019-02-28 for organic el element and method for manufacturing same.
This patent application is currently assigned to SUMITOMO CHEMICAL COMPANY, LIMITED. The applicant listed for this patent is SUMITOMO CHEMICAL COMPANY, LIMITED. Invention is credited to Shinichi MORISHIMA, Masato SHAKUTSUI, Masaya SHIMOGAWARA.
Application Number | 20190067626 15/768978 |
Document ID | / |
Family ID | 57582190 |
Filed Date | 2019-02-28 |
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United States Patent
Application |
20190067626 |
Kind Code |
A1 |
SHIMOGAWARA; Masaya ; et
al. |
February 28, 2019 |
ORGANIC EL ELEMENT AND METHOD FOR MANUFACTURING SAME
Abstract
An organic EL element comprises a supporting substrate 12 having
a first side surface 12b and a second side surface 12c located
opposite to the first side surface in the first direction, a first
electrode-attached on the supporting substrate, an organic EL body
16 disposed on the first electrode, a second electrode 18 disposed
extending from the first side surface to the second side surface
and covering at least a part of the organic EL body, and a sealing
member disposed on the second electrode, extending from the first
side surface to the second side surface and sealing at least the
organic EL body, each of the side surfaces 18a and 20a of the
second electrode and the sealing member on the first side
surface-side being made evened with the first side surface, and
each of the side surfaces 18b and 20b of the second electrode and
the sealing member on the second side surface-side being made
evened with the second side surface, in the first direction.
Inventors: |
SHIMOGAWARA; Masaya;
(Niihama-shi, JP) ; MORISHIMA; Shinichi;
(Tsukuba-shi, JP) ; SHAKUTSUI; Masato;
(Niihama-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SUMITOMO CHEMICAL COMPANY, LIMITED |
Tokyo |
|
JP |
|
|
Assignee: |
SUMITOMO CHEMICAL COMPANY,
LIMITED
Tokyo
JP
|
Family ID: |
57582190 |
Appl. No.: |
15/768978 |
Filed: |
June 6, 2016 |
PCT Filed: |
June 6, 2016 |
PCT NO: |
PCT/JP2016/066735 |
371 Date: |
April 17, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01L 51/5237 20130101;
H01L 51/5228 20130101; H01L 2251/5392 20130101; H01L 2251/556
20130101; H01L 2251/5361 20130101; H05B 33/22 20130101; H05B 33/04
20130101; H05B 33/06 20130101; H01L 51/5225 20130101; H01L 51/524
20130101; H05B 33/26 20130101; H01L 51/529 20130101; H01L 51/56
20130101; H05B 33/10 20130101; H01L 51/5209 20130101 |
International
Class: |
H01L 51/52 20060101
H01L051/52; H01L 51/56 20060101 H01L051/56 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 20, 2015 |
JP |
2015-206467 |
Claims
1. An organic EL element comprising: a supporting substrate having
a first side surface and a second side surface located opposite to
the first side surface in a first direction; a first electrode
disposed on the supporting substrate; an organic EL body disposed
on the first electrode and including a light emitting layer; a
second electrode disposed extending from the first side surface to
the second side surface, and covering at least a part of the
organic EL body; and a sealing member disposed on the second
electrode, extending from the first side surface to the second side
surface, and sealing at least the organic EL body; each of the side
surfaces of the second electrode and the sealing member on the
first side surface-side being made evened with the first side
surface, and each of the side surfaces of the second electrode and
the sealing member on the second side surface-side being made
evened with the second side surface, in the first direction.
2. The organic EL element according to claim 1, wherein the first
electrode has a first region and a second region adjacent to the
first region, in a second direction perpendicular to a thickness
direction of the supporting substrate and the first direction; the
organic EL body covers the first region; and an edge of the second
region on the opposite side of the first region is exposed from the
sealing member in the second direction.
3. The organic EL element according to claim 2, wherein the second
electrode covers a part of the organic EL body other than an edge
on the second region-side.
4. The organic EL element according to claim 3, wherein the edge of
the organic EL body on the second region-side is covered with a
hygroscopic part in the second direction.
5. The organic EL element according to claim 2, wherein the second
electrode covers the organic EL body; and an insulating layer is
disposed between the second region and the second electrode.
6. The organic EL element according to claim 2, wherein an
extracting electrode in electrically contact with the second
electrode is further disposed on the supporting substrate; the
extracting electrode is disposed on the opposite side of the second
region in the second direction when viewed from the first region;
and a part of the extracting electrode is exposed from the sealing
member.
7. The organic EL element according to claim 1, wherein the second
electrode comprises transition metal oxides, aluminum or
silver.
8. A method for manufacturing organic EL elements comprising: a
step of, while conveying a long electrode-attached substrate,
having a long supporting substrate and first electrodes disposed
respectively in a plurality of regions for forming organic EL
elements set in a longitudinal direction on the supporting
substrate, in the longitudinal direction, forming an organic EL
body including a light emitting layer on the first electrode in
each of the regions for forming organic EL elements; a step of,
while conveying the electrode-attached substrate including the
organic EL bodies formed thereon in the longitudinal direction,
forming a second electrode extending in the longitudinal direction
so as to cover at least a part of the organic EL bodies formed
respectively in a plurality of regions for forming organic EL
elements; a step of, while conveying the electrode-attached
substrate including the second electrode formed thereon in the
longitudinal direction, sticking a sealing member extending in the
longitudinal direction to the electrode-attached substrate from the
second electrode-side so as to seal at least the organic EL bodies
formed respectively in a plurality of regions for forming organic
EL elements; and a step of, while conveying the electrode-attached
substrate including the sealing member stuck thereto in the
longitudinal direction, cutting the electrode-attached substrate
for each of a plurality of the regions for forming organic EL
elements so as to obtain organic EL elements.
Description
TECHNICAL FIELD
[0001] The present invention relates to an organic EL element and a
method for manufacturing organic EL elements.
BACKGROUND ART
[0002] As an organic electroluminescence (EL) element, the organic
EL element described in Patent Literature 1 is known. The organic
EL element described in Patent Literature 1 has a substrate, a
first electrode layer including a plurality of transparent
electrodes disposed in the column direction on the substrate, an
organic layer disposed on the first electrode layer, and a second
electrode layer disposed on the organic layer, extending in the
column direction.
CITATION LIST
Patent Literature
[0003] Patent Literature 1: Japanese Unexamined Patent Publication
No. 2009-187774
SUMMARY OF INVENTION
Technical Problem
[0004] In the organic EL element described in Patent Literature 1,
the second electrode layer is disposed inside the edge of the
substrate, when viewed from the thickness direction of the
substrate. As described in Patent Literature 1, the second
electrode layer is made by forming a metal film (an aluminum film
in Patent Literature 1), to be the second electrode layer, on an
organic layer, which is then subjected to patterning by etching
utilizing photolithography technique to obtain a desired pattern.
In this case, because patterning of the metal film is required, the
productivity declines.
[0005] The present invention provides an organic EL element with
improved productivity, and a method for manufacturing organic EL
elements.
Solution to Problem
[0006] The organic EL element according to one aspect of the
present invention comprises a supporting substrate having a first
side surface and a second side surface located opposite to the
first side surface in a first direction, a first electrode disposed
on the supporting substrate, an organic EL body disposed on the
first electrode and including a light emitting layer, a second
electrode disposed extending from the first side surface to the
second side surface, and covering at least a part of the organic EL
body, and a sealing member disposed on the second electrode,
extending from the first side surface to the second side surface,
and sealing at least the organic EL body. In the first direction,
each of the side surfaces of the second electrode and the sealing
member on the first side surface-side is made evened with the first
side surface, and each of the side surfaces of the second electrode
and the sealing member on the second side surface-side is made
evened with the second side surface.
[0007] In the configuration described above, the second electrode
is disposed on the support substrate, extending from the first side
surface to the second side surface. In the first direction, each of
the side surfaces of the second electrode and the sealing member on
the first side surface-side is made evened with the first side
surface, and each of the side surfaces of the second electrode and
the sealing member on the second side surface-side is made evened
with the second side surface. When the second electrode is formed,
no patterning is therefore required at least in the first
direction. As a result, the productivity of organic EL elements can
be improved.
[0008] In an embodiment, the first electrode may have a first
region and a second region adjacent to the first region, in a
second direction perpendicular to a thickness direction of the
supporting substrate and the first direction; the organic EL body
may cover the first region; and an edge of the second region on the
opposite side of the first region may be exposed from the sealing
member in the second direction.
[0009] In this case, since the first region is covered with the
organic EL body, a short circuit between the first region and, for
example, the second electrode hardly occurs. Further, since the
second region is exposed from the sealing member, a voltage can be
applied to the first region by connecting an external connecting
terminal to the second region.
[0010] In an embodiment, the second electrode may cover a part of
the organic EL body other than an edge on the second
region-side.
[0011] In the second direction, the edge of the organic EL body on
the second region-side may be covered with a hygroscopic part.
[0012] In this case, the edge on the second region-side as a part
not covered with the second electrode in the organic EL body is
covered with the hygroscopic part. The moisture, therefore, hardly
reaches the organic EL body, so that deterioration of the organic
EL element can be further suppressed.
[0013] In an embodiment, the second electrode may cover the organic
EL body, and an insulating layer may be disposed between the second
region and the second electrode.
[0014] Since the organic EL body is covered with the second
electrode, moisture hardly reaches the organic EL body.
Deterioration of the organic EL element can be therefore further
suppressed. Since an insulating layer is disposed between the
second region and the second electrode, the short circuit between
the first and the second electrodes can be prevented, even though
the second electrode covers the organic EL body.
[0015] In an embodiment, an extracting electrode in electrically
contact with the second electrode may be further disposed on the
supporting substrate. The extracting electrode may be disposed on
the opposite side of the second region in the second direction when
viewed from the first region, and a part of the extracting
electrode may be exposed from the sealing member. A voltage can be
thereby applied to the second electrode through the extracting
electrode.
[0016] The second electrode may comprise transition metal oxides,
aluminum or silver.
[0017] A method for manufacturing organic EL elements according to
another aspect of the present invention comprises: a step of, while
conveying a long electrode-attached substrate having a long
supporting substrate and first electrodes disposed respectively in
a plurality of regions for forming organic EL elements set in the
longitudinal direction on the supporting substrate in the
longitudinal direction, forming an organic EL body including a
light emitting layer on the first electrode in each of the regions
for forming organic EL elements; a step of, while conveying the
electrode-attached substrate including the organic EL bodies formed
thereon in the longitudinal direction, forming a second electrode
extending in the longitudinal direction so as to cover at least a
part of the organic EL bodies formed respectively in a plurality of
regions for forming organic EL elements; a step of, while conveying
the electrode-attached substrate including the second electrode
formed thereon in the longitudinal direction, sticking a sealing
member extending in the longitudinal direction to the
electrode-attached substrate from the second electrode-side so as
to seal at least the organic EL bodies formed respectively in a
plurality of regions for forming organic EL elements; and a step
of, while conveying the electrode-attached substrate including the
sealing member stuck thereto in the longitudinal direction, cutting
the electrode-attached substrate for each of a plurality of the
regions for forming organic EL elements so as to obtain organic EL
elements.
[0018] In the manufacturing method, while a long electrode-attached
substrate including organic EL bodies formed thereon is being
conveyed, a long second electrode is formed over a plurality of
regions for forming organic EL elements. Subsequently, while the
electrode-attached substrate having the second electrode formed
thereon is being conveyed in the longitudinal direction, a sealing
member extending in the longitudinal direction is stuck to the
electrode-attached substrate from the second electrode-side so as
to seal the organic EL bodies. Subsequently, the electrode-attached
substrate is cut for each of a plurality of the regions for forming
organic EL elements so as to obtain organic EL elements. The
organic EL elements of the present invention can be thereby
suitably manufactured. In this method, the second electrode of each
of the organic EL elements is formed by forming the second
electrode over a plurality of the regions for forming organic EL
elements and then cutting the electrode in the longitudinal
direction. No patterning of the second electrode is therefore
required at least in the longitudinal direction of the
electrode-attached substrate, so that the productivity of the
organic EL elements is improved.
Advantageous Effects of Invention
[0019] According to the present invention, an organic EL element
and a method for manufacturing organic EL elements with improved
productivity are provided.
BRIEF DESCRIPTION OF DRAWINGS
[0020] FIG. 1 is a plan view of an organic EL element in an
embodiment.
[0021] FIG. 2 (a) is a cross-sectional view taken from line IIa-IIa
in FIG. 1, and FIG. 2 (b) is a cross-sectional view taken from line
IIb-IIb in FIG. 1.
[0022] FIG. 3 is a top view of a long electrode attached substrate
for use in the method for manufacturing organic EL elements.
[0023] FIG. 4 is a schematic diagram illustrating the method for
manufacturing organic EL elements by a roll-to-roll method.
[0024] FIG. 5 is a diagram illustrating a step of forming
bodies.
[0025] FIG. 6 is a diagram illustrating a step of forming
cathodes.
[0026] FIG. 7 is a diagram illustrating a step of sealing.
[0027] FIG. 8 is a diagram illustrating a step of sealing.
[0028] FIG. 9 is a diagram illustrating a step of sealing by a
roll-to-roll method.
[0029] FIG. 10 (a) is a diagram illustrating a step of cutting, and
FIG. 10 (b) is the side view of an organic EL element cut out from
an electrode-attached substrate in the step of cutting.
[0030] FIG. 11 is a plan view of an organic EL element in other
embodiment.
[0031] FIG. 12 (a) is a cross-sectional view taken from line
XIIa-XIIa in FIG. 11, and FIG. 12 (b) is a cross-sectional view
taken from line XIIb-XIIb in FIG. 11.
[0032] FIG. 13 is a plan view of an organic EL element in a still
other embodiment.
[0033] FIG. 14 is a cross-sectional view taken from line XIV-XIV in
FIG. 13.
[0034] FIG. 15 is a cross-sectional view of an organic EL element
in a still other embodiment.
DESCRIPTION OF EMBODIMENTS
[0035] With reference to attached drawings, preferred embodiments
of the present invention are described in detail as follows. In the
description of drawings, the same symbols are used for the same or
equivalent elements, and redundant descriptions are omitted.
[0036] As shown in FIG. 1, FIG. 2 (a) and FIG. 2 (b), an organic EL
element 10 in an embodiment comprises a supporting substrate 12, an
anode (first electrode) 14, an organic EL body 16, a cathode
(second electrode) 18, and a sealing member 20. In an embodiment,
the organic EL element 10 may comprise an extracting electrode 22.
Hereinafter, configurations including the extracting electrode 22
are described unless otherwise noted.
[0037] For convenience of explanation, as shown in FIG. 1, FIG. 2
(a), and FIG. 2 (b), the thickness direction of the supporting
substrate 12 is referred to as Z-axis direction, and the directions
perpendicular to the Z-axis direction are referred to also as
X-axis direction (first direction) and Y-axis direction (second
direction). The X-axis direction and the Y-axis direction are
perpendicular to each other. The X-axis direction corresponds to
the conveying direction of the supporting substrate 12 and the
Y-axis direction corresponds to the width direction of the
supporting substrate 12 in a method for manufacturing organic EL
elements 10 to be described below.
[0038] [Supporting Substrate]
[0039] A supporting substrate 12 is made of a resin having
translucency to visible light (light with a wavelength ranging from
400 nm to 800 nm). The supporting substrate 12 may be a film-like
substrate. In a first embodiment, the supporting substrate 12 has
flexibility. The thickness of the supporting substrate 12 is, for
example, 30 .mu.m or more and 500 .mu.m or less.
[0040] The supporting substrate 12 is, for example, a plastic film.
The material of the supporting substrate 12 includes, for example,
polyether sulfone (PES); polyester resins such as polyethylene
terephthalate (PET) and polyethylene naphthalate (PEN); polyolefin
resins such as polyethylene (PE), polypropylene (PP), and cyclic
polyolefins; polyamide resins; polycarbonate resins; polystyrene
resins; polyvinyl alcohol resins; saponified ethylene-vinyl acetate
copolymers; polyacrylonitrile resins; acetal resins; polyimide
resin; and epoxy resins.
[0041] Among the resins as the material for the supporting
substrate 12, polyester resins and polyolefin resins are preferable
and polyethylene terephthalate and polyethylene naphthalate are
particularly preferable, because of high heat resistance, a low
linear expansion coefficient, and low manufacturing cost. One of
these resins may be used alone, or two or more of these may be used
in combination.
[0042] On a main surface 12a of the supporting substrate 12, a
barrier film may be disposed. The barrier film may be a film
comprising, for example, silicon, oxygen and carbon, or may be a
film comprising silicon, oxygen, carbon and nitrogen. Specifically,
examples of the barrier film material include silicon oxide,
silicon nitride, and silicon oxynitride. The thickness of the
barrier film is, for example, 100 nm or more and 10 .mu.m or
less.
[0043] [Anode]
[0044] An anode 14 is disposed on the main surface 12a of the
supporting substrate 12. As the anode 14, an electrode layer
exhibiting optical transparency is used. As the electrode
exhibiting optical transparency, a thin film of metal oxides, metal
sulfides, metals or the like having high electric conductivity can
be used, and a thin film having a high light transmittance is
suitably used. For example, a thin film consisting of indium oxide,
zinc oxide, tin oxide, indium tin oxide (abbreviation: ITO), indium
zinc oxide (abbreviation: IZO), gold, platinum, silver, copper or
the like is used, and, among these, a thin film consisting of ITO,
IZO, or tin oxide is suitably used. As the anode 14, a transparent
conductive film of organic material such as polyaniline and
derivatives thereof and polythiophene and derivatives thereof may
be also used. The anode 14 may have a network structure consisting
of a conductor (e.g., metal).
[0045] The thickness of the anode 14 may be determined by taking
into consideration the translucency of light, electric conductivity
and the like. The thickness of the anode 14 is usually 10 nm to 10
.mu.m, preferably 20 nm to 1 .mu.m, more preferably 50 nm to 500
nm.
[0046] Examples of the method for forming the anode 14 include
vacuum deposition, sputtering, ion plating, plating and
coating.
[0047] The anode 14 has an anode body (first region) 141 covered
with the organic EL body 16 and a part not covered with the organic
EL body 16, i.e., an external connecting part (second region) 142
as remaining part other than the anode body 141. The external
connecting part 142 is disposed in the Y-axis direction when viewed
from the anode body 141, adjacent to the anode body 141. A part of
the external connecting part 142 is pulled out from the sealing
member 20, and the external connecting part 142 functions as a
connection region for connecting an external connecting terminal to
the anode 14.
[0048] [Extracting Electrode]
[0049] An extracting electrode 22 is disposed at a predetermined
distance from the anode 14. In an embodiment shown in FIG. 1, the
extracting electrode 22 is disposed on the opposite side of the
external connecting part 142 of the anode 14 in the Y-axis
direction. The extracting electrode 22 is electrically connected to
the cathode 18, functioning as a connection region for electrically
connecting an external connecting terminal to the cathode 18 so as
to apply a voltage to the cathode 18. The thickness of the
extracting electrode 22 is equivalent to the thickness of the anode
14. The material of the extracting electrode 22 is the same as the
material of the anode 14.
[0050] [Organic EL Body]
[0051] An organic EL body 16 including a light emitting layer 161
is a functional part to contribute light emission of the organic EL
element 10, moving carriers and recombining carriers corresponding
to the voltage applied to the anode 14 and the cathode 18. In the
example shown in FIG. 1, FIG. 2 (a) and FIG. 2 (b), the organic EL
body 16 has a single-layer structure including a light emitting
layer 161.
[0052] The light emitting layer 161 is an organic layer disposed on
the anode 14. The light emitting layer 161 is typically formed of
mainly an organic material emitting fluorescence and/or
phosphorescence or the organic material and a dopant to assist the
same. The dopant is added, for example, to improve luminous
efficiency or to change the emission wavelength. The organic
material contained in the light emitting layer 161 may be a
low-molecular compound or a high-molecular compound. Examples of
the light emitting material to constitute the light emitting layer
161 include known dye materials, metal complex materials, polymer
materials, and dopant materials.
[0053] The thickness of the light emitting layer 161 is typically
about 2 nm to 200 nm. The light emitting layer 161 is formed by the
coating method with use of a coating liquid containing the light
emitting material. The solvent of the coating liquid containing the
light emitting material is not limited as long as the light
emitting material is dissolved therein. Examples of the coating
method include ink jet printing, though any other known coating
method may be employed.
[0054] The organic EL body 16 is disposed to cover the anode body
141 of the anode 14. The short circuit between the anode body 141
and other electrodes (e.g., cathode 18 and extracting electrode 22)
is thereby prevented. Since the organic EL body 16 covers the anode
body 141 of the anode 14, a part of the organic EL body 16 is
disposed also on the main surface 12a of the supporting substrate
12.
[0055] As described above, an embodiment in which the organic EL
body 16 is a light emitting layer 161 is shown as an example in
FIG. 1, FIG. 2 (a) and FIG. 2 (b), the organic EL body 16 may be a
laminate including the light emitting layer 161 and other
functional layers. An example of the layer configuration in this
case is described as follows.
[0056] Examples of the functional layer disposed between the anode
14 and the light emitting layer 161 include a hole injection layer
and a hole transport layer. Examples of the layer disposed between
the cathode 18 and the light emitting layer 161 include an electron
injection layer and an electron transport layer. Known materials
may be used as the materials for the hole injection layer, the hole
transport layer, the electron transport layer and the electron
injection layer, respectively. The thickness of the hole injection
layer, the hole transport layer, the electron transport layer and
the electron injection layer may be appropriately set depending on
the element performance of the organic EL element 10.
[0057] The hole injection layer is a layer having a function to
improve the hole injection efficiency from the anode 14 to the
light emitting layer 161. The hole transport layer is a layer
having a function to improve the hole injection into the light
emitting layer 161 from the anode 14, the hole injection layer or
the hole transport layer closer to the anode 14. When the hole
injection layer and/or the hole transport layer have a function to
block the transport of electrons, these layers may be referred to
also as electron blocking layers.
[0058] The electron injection layer is a layer having function to
improve the electron injection efficiency from the cathode 18 to
the light emitting layer 161. As described below, the electron
injection layer constitutes a part of the cathode 18 in some cases.
The electron transport layer is a layer having a function to
improve the electron injection from the cathode 18, the electron
injection layer or the electron transport layer closer to the
cathode 18. In the case where the electron injection layer and/or
the electron transport layer have a function to block the transport
of holes, these layers may be referred to also as hole blocking
layers in some cases.
[0059] Examples of the layer configuration of the organic EL
element 10 including the various functional layers described above
are as follows.
[0060] a) anode/light emitting layer/cathode
[0061] b) anode/hole injection layer/light emitting
layer/cathode
[0062] c) anode/hole injection layer/light emitting layer/electron
injection layer/cathode
[0063] d) anode/hole injection layer/light emitting layer/electron
transport layer/electron injection layer/cathode
[0064] e) anode/hole injection layer/hole transport layer/light
emitting layer/cathode
[0065] f) anode/hole injection layer/hole transport layer/light
emitting layer/electron injection layer/cathode
[0066] g) anode/hole injection layer/hole transport layer/light
emitting layer/electron transport layer/electron injection
layer/cathode
[0067] h) anode/light emitting layer/electron injection
layer/cathode
[0068] i) anode/light emitting layer/electron transport
layer/electron injection layer/cathode
[0069] The symbol "/" means that the layers on both sides of the
symbol "/" are joined to each other. The configuration a) described
above corresponds to the configuration shown in FIG. 1 to FIG.
3.
[0070] The organic EL element 10 may have a single light emitting
layer 161 or may have two or more light emitting layers 161. In any
one of the layer configurations a) to i) described above, a
laminate structure disposed between the anode 14 and the cathode 18
is defined as "structural unit A". Examples of the configuration of
the organic EL element 10 having two light emitting layers 161
include a layer configuration j) described below. The layer
configurations of the two (structural units A) may be the same or
different from each other.
[0071] j) anode/(structural unit A)/charge generation
layer/(structural unit A)/cathode
[0072] In this specification, the charge generation layer is a
layer for generating holes and electrons by application of an
electric field. Examples of the charge generation layer may include
a thin film consisting of vanadium oxide, ITO, molybdenum oxide, or
the like.
[0073] With "(structural unit A)/charge generation layer" defined
as "structural unit B", examples of the configuration of the
organic EL element 10 having three or more-layered light emitting
layers 161 include a layer configuration k) described below.
[0074] k) anode/(structural unit B)x/(structural unit
A)/cathode
[0075] The symbol "x" represents an integer of 2 or more, and
"(structural unit B)x" represents a laminate including x-layered
(structural units B). The layer configurations of a plurality of
the (structural units B) may be the same or different.
[0076] A plurality of light emitting layers 161 may be directly
laminated without a charge generation layer so as to configure the
organic EL element 10.
[0077] [Cathode]
[0078] A cathode 18 is disposed on the organic EL body 16 so as to
cover at least a part of the organic EL body 16. The cathode 18 is
disposed so as to extend between the side surface (first side
surface) 12b and the side surface (second side surface) 12c which
are both side surfaces of the supporting substrate 12 in the X-axis
direction. In the first embodiment, the cathode 18 is disposed to
cover a part of the organic EL body 16 other than an edge 16a on
the external connecting part 142 side of the anode 14 (refer to
FIG. 2 (b)) for prevention of the short circuit to the anode 14. In
other words, the cathode 18 is disposed such that the edge 16a of
the organic EL body 16 on the external connecting part 142 side is
exposed from the cathode 18 when viewed from the thickness
direction of the supporting substrate 12, and the cathode 18 is
disposed also on a main surface 12a of the supporting substrate
12.
[0079] As a result, in an embodiment with an extracting electrode
22 provided therein, the cathode 18 is disposed also on the main
surface 12a between the extracting electrode 22 and the anode 14,
and the cathode 18 and the extracting electrode 22 are connected as
shown in FIG. 2 (b). Even with the cathode 18 being disposed, since
the anode body 141 is covered with the organic EL body 16 as
described above, the short circuit between the cathode 18 and the
anode 14 is prevented. Examples of the material of the cathode 18
are described below.
[0080] The thickness of the cathode 18 is set by taking into
consideration the electric conductivity and the durability. The
thickness of the cathode 18 is typically 10 nm to 10 .mu.m,
preferably 20 nm to 1 .mu.m, more preferably 50 nm to 500 nm.
[0081] [Sealing Member]
[0082] A sealing member 20 is disposed on the cathode 18 so as to
embed the organic EL body 16. The sealing member 20 is disposed on
the supporting substrate 12 and extends between the side surfaces
12b and 12c of the supporting substrate 12 so as to seal at least
the organic EL body 16. The width of the sealing member 20 in the
Y-axis direction is narrower than the width of the supporting
substrate 12, and the sealing member 20 is disposed on the
supporting substrate 12 such that a part of the external connecting
part 142 and a part of the extracting electrode 22 are exposed (or
pulled out) from the sealing member 20. The sealing member 20 has a
sealing substrate 201 and an adhesive part 202.
[0083] The sealing substrate 201 is disposed on the opposite side
of the supporting substrate 12 in the organic EL element 10. The
sealing substrate 201 consists of a metal foil, a barrier film
including a transparent plastic film of which the front face, the
rear face, or both faces have a functional barrier layer, a thin
film glass having flexibility, a plastic film on which a metal
having barrier properties is laminated, or the like, and has a gas
barrier function, in particular, moisture barrier function. As the
metal foil, a copper foil, an aluminum foil, and a stainless steel
foil are preferred from the viewpoint of barrier properties.
Although it is more preferable to increase the thickness of the
metal foil from the viewpoint of preventing pinholes, a thickness
of 15 .mu.m to 50 .mu.m is preferred considering the viewpoint of
flexibility.
[0084] The adhesive part 202 is disposed on the surface of the
sealing substrate 201 on the supporting substrate 12 side for use
to stick the sealing substrate 201 to the supporting substrate 12
having the anode 14, the organic EL body 16 and the cathode 18
formed thereon. The adhesive part 202 covers at least the anode
body 141, the organic EL body 16, and a part of the cathode 18
other than both side surfaces in the X-axis direction, i.e., the
side surfaces 18a and 18b. In the following description, the part
covered with the adhesive part 202 in the configuration of the
supporting substrate 12 is referred to as the covered part. The
thickness of the adhesive part 202 may be any thickness that allows
the covered part to be covered, for example, 1 .mu.m to 100 .mu.m,
preferably 5 .mu.m to 60 .mu.m, more preferably 10 .mu.m to 30
.mu.m.
[0085] Specifically, the adhesive part 202 is made from a
photocurable or thermosetting acrylate resin, or a photocurable or
thermosetting epoxy resin. Alternatively, a resin film that can be
fused by a commonly used impulse sealer, e.g., a heat sealable film
such as an ethylene vinyl acetate copolymer (EVA), a polypropylene
film, a polyethylene film and a polybutadiene film, may be used.
Further, a thermoplastic resin may be also used.
[0086] As the adhesive for use in the adhesive part 202, an
adhesive that achieves high adhesion between the covered part
covered with the adhesive part 202 and the adhesive part 202, and
has high effects for suppressing the marked thermal contraction of
the adhesive, the detachment of the covered part due to a stress
applied to the covered part, the generation of components having a
bad effect on the covered part from the adhesive part 202, and the
generation and growth of dark spots with high barrier properties,
is preferred.
[0087] As shown in FIG. 2 (a), the side surface 12b of the
supporting substrate 12, the side surface 18a of the cathode 18,
and the side surface 20a of the sealing member 20 are made evened
in the X-axis direction of the organic EL element 10. In other
words, the side surface 18a of the cathode 18 is disposed at the
same position as the side surface 12b and the side surface 20a in
the X-axis direction. In the first embodiment, the side surface 18a
is flushed with the side surface 12b and the side surface 20a.
Similarly, the side surface 12c on the opposite side of the side
surface 12b of the supporting substrate 12, the side surface 18b on
the opposite side of the side surface 18a of the cathode 18, and
the side surface 20b on the opposite side of the side surface 20a
of the sealing member 20 are made evened, in the X-axis direction
of the organic EL element 10. In other words, the side surface 18b
of the cathode 18 is disposed at the same position as the side
surface 12c and the side surface 20b in the X-axis direction. In
the first embodiment, the side surface 18b is flushed with the side
surface 12c and the side surface 20b.
[0088] In this configuration, the side surfaces 18a and 18b of the
cathode 18 are exposed without covered by the sealing member 20. It
is therefore preferable that the material for the cathode 18 be a
material that is substantially insensitive to the moisture effect.
From this viewpoint, examples of the material for the cathode 18
include transition metal oxides, aluminum and silver. The cathode
18 may be made from one metal or an alloy of the metals described
above as examples. Further, the cathode may have a multi-layer
structure.
[0089] With reference to FIG. 3 to FIG. 10, a method for
manufacturing organic EL elements 10 is described as follows. In
this specification, as shown in FIG. 3, a method for manufacturing
organic EL elements 10, using roll-to-roll method, from a long
electrode attached substrate 24 having a long and flexible
supporting substrate 12, a plurality of cathodes 14 and a plurality
of extracting electrodes 22 and in which the plurality of cathodes
14 are discretely disposed in the longitudinal direction is
described.
[0090] A plurality of regions 26 for forming organic EL elements
are virtually disposed on the main surface 12a of the long
supporting substrate 12, and an anode 14 and an extracting
electrode 22 are disposed on each of the regions 26 for forming
organic EL elements. Accordingly, the numbers of the anodes 14 and
the extracting electrodes 22 are the same, and one extracting
electrode 22 is disposed corresponding to one anode 14, at a
predetermined distance in the direction perpendicular to the
longitudinal direction of the supporting substrate 12 (hereinafter,
referred to also as "width direction"). The anode 14 and the
extracting electrode 22 can be formed, for example, by forming an
electrode film to make the anode 14 and the extracting electrode 22
and then processing the electrode film into a predetermined pattern
using, for example, fine processing technology such as
photolithography.
[0091] In the example shown in FIG. 3, the side surface 14a of the
anode 14 is formed at the same position as the edge 24a of the
electrode-attached substrate 24, and the side surface 22a of the
extracting electrode 22 is formed at the same position as the edge
24b on the opposite side of the edge 24a of the electrode-attached
substrate 24. The anode 14, however, may be formed at a certain
distance away from the edge 24a, and the extracting electrode 22
also may be formed at a certain distance away from the edge 24b, in
the width direction of the electrode-attached substrate 24.
[0092] The method for manufacturing organic EL elements 10
comprises a body-forming step S10 of forming organic EL body 16, a
cathode-forming step S12 of forming a cathode 18, a sealing step
S14 of sealing the organic EL body 16 with a sealing member 20, and
a cutting step S16 of cutting out the organic EL elements 10. In
the first embodiment, as conceptually shown in FIG. 4, while a long
flexible electrode-attached substrate 24 stretched between an
unwinding roll 28A and winding roll 28B is being continuously
conveyed with conveying rollers 30, the body-forming step S10, the
cathode-forming step S12, and the sealing step S14 are performed by
a roll-to-roll method, and then the cutting step S16 is performed.
Each of the steps is described in detail as follows.
[0093] (Organic EL Body-Forming Step)
[0094] In a body-forming step S10, while the electrode-attached
substrate 24 is being conveyed in the longitudinal direction
thereof, the organic EL body 16 is formed, for example, by the
coating method such that the anode 14 the edge 24b side of the
electrode-attached substrate 24 is covered and the anode 14 on the
edge 24a side is exposed as shown in FIG. 5. For example, as shown
in FIG. 5, in the case where the organic EL body 16 is a light
emitting layer 161, a coating liquid containing a material to make
the light emitting layer 161 is applied to the region for forming
the organic EL body 16 and dried, so that the light emitting layer
161 as the organic EL body 16 is formed. Examples of the coating
method include an ink-jet printing method.
[0095] In an embodiment with the organic EL body 16 having
functional layers other than the light emitting layer 161, each of
the functional layers may be sequentially formed from the anode 14
side while the electrode-attached substrate 24 is being conveyed,
by the same method as for the light emitting layer 161 described
above. The method for forming the organic EL body 16 is not limited
to the coating method as long as the organic EL body 16 can be
formed.
[0096] In the anode 14, the region covered with the organic EL body
16 is an anode body 141 shown in FIG. 1, FIG. 2 (a) and FIG. 2 (b),
and the region exposed from the organic EL body 16 is an external
connecting part 142.
[0097] (Cathode-Forming Step)
[0098] In a cathode-forming step S12, while the electrode-attached
substrate 24 is being conveyed in the longitudinal direction
thereof, the cathode 18 is formed on the organic EL body 16 as
shown in FIG. 6. On this occasion, in the first embodiment, the
cathode 18 is formed such that the edge 16a of the organic EL body
16 on the external connecting part 142 side is exposed in the width
direction of the electrode-attached substrate 24. Also, the cathode
18 is formed to come in contact with the extracting electrode 22.
In this case, the cathode 18 may be formed to cover a part of the
extracting electrode 22 as shown in FIG. 6.
[0099] The cathode 18 is continuously formed over a plurality of
regions 26 for forming organic EL elements along the longitudinal
direction of the electrode-attached substrate 24. In other words,
the cathode 18 formed in the cathode forming-step S12 is a long
cathode 18 extending along the conveying direction. Examples of the
method for forming the cathode 18 include the coating method which
is the same as in forming of the organic EL body 16. The cathode
18, however, may be formed by vacuum deposition, sputtering, or a
laminating method for thermally compressing a metal film.
[0100] In an embodiment with the cathode 18 having a laminate
structure, each of the layers to be the cathode 18 may be
sequentially formed from the layer located at the organic EL body
16 side while the electrode-attached substrate 24 is being conveyed
in the longitudinal direction.
[0101] (Sealing Step)
[0102] In the sealing step S14, while the electrode-attached
substrate 24 having the cathode 18 formed thereon is being conveyed
in the longitudinal direction, the sealing member 20 is stuck to
the electrode-attached substrate 24 over a plurality of regions 26
for forming organic EL elements from the cathode 18 side, so that
the organic EL body 16 is sealed with the sealing member 20. By the
sealing step S14, an electrode-attached substrate 24 on which the
sealing member 20 extending in the longitudinal direction is stuck
to over a plurality of the regions 26 for forming organic EL
elements is obtained as shown in FIG. 7.
[0103] Specifically, in the sealing step S14, the sealing member 20
is stuck to the electrode-attached substrate 24, which has been
subjected to the cathode-forming step S12, from the cathode 18 side
as shown in FIG. 8. On this occasion, the sealing member 20 is
stuck to the electrode-attached substrate 24 such that the adhesive
part 202 side of the sealing member 20 is located on the
electrode-attached substrate 24. The width of the sealing member 20
is narrower than the width of the electrode-attached substrate 24
as shown in FIG. 7, and the sealing member 20 is stuck: to the
electrode-attached substrate 24 such that a part of the external
connecting part 142 of the anode 14 and a part of the extracting
electrode 22 are exposed.
[0104] In the roll-to-roll method, as schematically shown in FIG.
9, while the electrode-attached substrate 24 is being conveyed, the
long sealing member 20 is continuously stuck onto the
electrode-attached substrate 24 having cathodes 18 formed thereon
from the cathode 18 side. The electrode-attached substrate 24 and
the sealing member 20 pass between heating rollers 32a and 32b. As
a result, the electrode-attached substrate 24 and the sealing
member 20 are heated under pressure with the heating rollers 32a
and 32b. The adhesive part 202 is thereby softened to make close
contact with the components on the electrode-attached substrate 24
that is to be covered with the adhesive part 202. In FIG. 9, the
illustration of the configuration on the electrode-attached
substrate 24 and the configuration of the sealing member 20 is
omitted.
[0105] As conceptually shown in FIG. 4, in the first embodiment,
the electrode-attached substrate 24 having long cathodes 18 formed
thereon is wound around a winding roll 28B after the
cathode-forming step S12.
[0106] (Cutting Step)
[0107] In the cutting step S16, the electrode-attached substrate 24
once wound after the sealing step S14 is further reeled out to be
conveyed in the longitudinal direction of the electrode-attached
substrate 24 with conveying rollers 30 as shown in FIG. 10 (a).
While being conveyed in the longitudinal direction, the
electrode-attached substrate 24 is cut at between the adjacent
regions 26 for forming organic EL elements in the width direction
of the electrode-attached substrate 24, so that the organic EL
elements 10 are obtained as shown in FIG. 10 (b). In FIG. 10 (a), a
cutting apparatus 34 is schematically shown.
[0108] In the method for manufacturing organic EL elements 10 shown
above as an example, the steps other than the cutting step S16 are
continuously performed by a roll-to-roll method. In the case where
spaces are disposed between the edges 24a and 24b of the
electrode-attached substrate 24, and the regions 26 for forming
organic EL elements, the cutting step S16 may be included in the
roll-to-roll method ranging to the sealing step S14, provided that
the regions 26 for forming organic El elements are cut out from the
electrode-attached substrate 24 in the cutting step S16 and a part
of the electrode-attached substrate 24 remains to be conveyed.
[0109] On the contrary, the roll-to-roll method may be employed for
each of the body-forming step S10, the cathode-forming step S12,
and the sealing step S14. In other words, in each of the
body-forming step S10, the cathode-forming step S12, and the
sealing step S14, the electrode-attached substrate 24 may be wound
once, and then a subsequent step may be performed.
[0110] Although the electrode-attached substrate 24 is prepared in
advance in the manufacturing method described above, for example, a
step for forming anodes 14 and extracting electrodes 22 on a long
supporting substrate 12 may be further provided.
[0111] In the organic EL element 10, the cathode 18 extends in a
predetermined direction (the X-axis direction in FIG. 1). In other
words, the cathode 18 is disposed extending from the side surface
12b to the side surface 12c of the supporting substrate 12 as shown
in FIG. 1 and FIG. 2 (a). Consequently, as long as the width in the
direction perpendicular to a predetermined direction (the Y-axis
direction or the width direction) is controlled in manufacturing
the organic EL elements 10, patterning of the cathode 18 in the
predetermined direction is not required. The manufacturing of
organic EL elements 10 is therefore easy. In particular, when an
ink-jet printing method is employed, the width in the direction
perpendicular to a predetermined direction of the cathode 18 (the
Y-axis direction or the width direction) can be easily controlled,
for example, by selecting the nozzle to discharge a coating
liquid.
[0112] An organic EL element 10 having both side surfaces of a
supporting substrate 12, a cathode 18, and a sealing member 20 made
evened, respectively, can be suitably manufactured by the method
for manufacturing organic EL elements 10. Specifically, as shown as
an example, while the electrode-attached substrate 24 is being
conveyed in the longitudinal direction thereof, a long cathode 18
is continuously formed in the conveying direction, and an organic
EL body 16 is then sealed with a sealing member 20. Subsequently
the organic EL body 16 is cut at a predetermined position to obtain
organic EL elements 10. As a result, cathode patterning required
for an embodiment with a cathode embedded in a sealing member is
unnecessary. Accordingly, in the method for manufacturing organic
EL elements 10, the productivity of organic EL elements 10 is
improved. Further, such a manufacturing method described above is
suitable for manufacturing by a roll-to-roll method shown as an
example. In the roll-to-roll method, each of the steps in the
method for manufacturing organic EL elements 10 can be continuously
performed while the long electrode-attached substrate 24 is being
conveyed, so that the productivity is further improved.
[0113] In the organic EL element 10, although the side surface 18a
and the side surface 18b of the cathode 18 are exposed without
cover of the sealing member 20, deterioration of the organic EL
element 10 can be prevented by using a material not sensitive to
moisture as the cathode 18.
Second Embodiment
[0114] With reference to FIG. 11, FIG. 12 (a) and FIG. 12 (b), an
organic EL element 10A in a second embodiment is described. The
organic EL element 10A includes an insulating layer 36 on the anode
14, which is different mainly from the configuration of the organic
EL element 10. Focusing on the difference, the organic EL element
10A is described. Unless otherwise noted, in the second embodiment
also, an organic EL body 16 has a single layer structure including
a light emitting layer 161.
[0115] The insulating layer 36 is disposed adjacent to the organic
EL body 16 on an external connecting part 142. A part of the
organic EL body 16 may be disposed on the insulating layer 36.
Examples of the material for the insulating layer 36 include
photosensitive polyimide resins, acrylic resins, epoxy resins, and
phenol resins, and specifically including resist materials. The
thickness of the insulating layer 36 is, for example, 0.1 .mu.m to
10 .mu.m.
[0116] In the organic EL element 10A, a cathode 18 covers an edge
16a of the organic EL body 16 also, and the cathode 18 is formed
also on the insulating layer 36 as shown in FIG. 12 (a) and FIG. 12
(b). In other words, the insulating layer 36 is disposed between
the cathode 18 and an external connecting part 142.
[0117] The organic EL elements 10A can be manufactured by the same
method as for manufacturing the organic EL elements 10, except that
an insulating layer-forming step for forming the insulating layer
36 is provided before the cathode-forming step S12 shown in FIG. 4.
In the insulating layer-forming step, while the electrode-attached
substrate 24 is being conveyed in the longitudinal direction
thereof, the insulating layer 36 may be formed, for example, by a
coating method. Examples of the coating method include an ink-jet
printing method.
[0118] The insulating layer-forming step may be appropriately
performed before the cathode-forming step S12, corresponding to the
configuration of the organic EL body 16 and the arrangement
relation of the insulating layer 36 relative to the organic EL body
16.
[0119] For example, as shown in FIG. 11, FIG. 12 (a) and FIG. 12
(b), in the configuration where the organic EL body 16 includes the
light emitting layer 161 only and the organic EL body 16 is
disposed to cover a part of the insulating layer 36, the insulating
layer-forming step is performed before the body-forming step
S10.
[0120] In the case where the organic EL body 16 has a multi-layer
structure including the light emitting layer 161 and in the
configuration that the organic EL body 16 is disposed to cover a
part of the insulating layer 36, the insulating layer-forming step
may be performed, for example, before the-body forming step S10 or
in the body-forming step S10.
[0121] In the case where the insulating layer-forming step is
performed before the body-forming step S10, among a plurality of
functional layers to constitute the organic EL body 16, each of the
functional layers are formed adjacent to the insulating layer 36
until reaching the same thickness as that of the insulating layer
36, and after exceeding the thickness of the insulating layer 36,
the remaining functional layers are fainted to cover a part of the
insulating layer 36, in the body-forming step S10.
[0122] In the case where the insulating layer-forming step is
performed in the body-forming step S10, the insulating layer 36 is
formed after formation of a predetermined number of functional
layers among a plurality of functional layers to constitute the
organic EL body 16, in the body-forming step S10. The remaining
functional layers of the organic EL body 16 may be then formed to
cover a part of the insulating layer 36. The predetermined number
is the number of functional layers that allows the total thickness
of the predetermined number of functional layers reaches the
substantially same thickness as that of the insulating layer 36 in
design.
[0123] In the configuration with the organic EL body 16 not
covering a part of the insulating layer 36, the insulating
layer-forming step may be performed before the organic EL
body-forming step S10 or between the body-forming step S10 and the
cathode-forming step S12.
[0124] The organic EL element 10A has substantially the same
configuration as that of the organic EL element 10, except that the
organic EL element 10A includes an insulating layer 36 on the anode
14, which is mainly different from the configuration of the organic
EL element 10. The organic EL element 10A, therefore, achieves at
least the effects similar to those of the organic EL element
10A.
[0125] In the organic EL element 10A, the insulating layer 36 is
disposed between the anode 14 and the cathode 18, so that the short
circuit between the anode 14 and the cathode 18 is more reliably
prevented. Since the organic EL body 16 including an edge 16a is
covered with the cathode 18, the moisture hardly reaches the
organic EL body 16, so that deterioration of the organic EL body
caused by the moisture can be further prevented. The life of the
organic EL element 10A can be, therefore, prolonged.
Third Embodiment
[0126] With reference to FIG. 13 and FIG. 14, an organic EL element
10B in a third embodiment is described as follows. The organic EL
element 10B includes a hygroscopic part 38, which is mainly
different from the configuration of the organic EL element 10.
Focusing on the difference, the organic EL element 10B is described
as follows.
[0127] The hygroscopic part 38 is a desiccant for capturing
moisture. The hygroscopic part 38 may capture oxygen or the like
other than moisture. The hygroscopic part 38 is disposed to cover
an edge 16a of the organic EL body 16 exposing from a cathode 18 on
the external connecting part 142 side. The shape of the hygroscopic
part 38 is not limited as long as the edge 16a can be covered.
[0128] It is preferable that the hygroscopic rate of the
hygroscopic part 38 be 1 wt %/h or more under an environment at a
temperature of 24.degree. C. and a humidity of 55% RH.
[0129] The organic EL elements 10B can be manufactured by the same
method as for manufacturing the organic EL elements 10, except that
a hygroscopic part-forming step for forming the hygroscopic part 38
is provided between the body-forming step S10 and the
cathode-forming step S12 shown in FIG. 4.
[0130] In the hygroscopic part-forming step, while the
electrode-attached substrate 24 which has been subjected to the
body-forming step S10 are being conveyed in the longitudinal
direction thereof, the hygroscopic part 38 may be formed, for
example, by a coating method. Examples of the coating method
include an ink-jet printing method.
[0131] Specifically, a coating liquid containing a liquid getter
material as precursor of the hygroscopic part 38 is applied to a
predetermined position of the organic EL body 16 by a coating
method, so as to form the hygroscopic part 38. Specifically, the
coating liquid is applied onto the organic EL body 16 and the
external connecting part 142 so as to cover the edge 16a of the
organic EL body 16. Subsequently, after the coating liquid is
dried, the liquid getter material is cured to form into the
hygroscopic part 38. The liquid getter material may include a
cross-linkable compound having a photoreactive group (curing
component). In this case, after the application and shaping of the
liquid getter material, the hygroscopic part 38 is formed by
performing a UV irradiation treatment to cure the liquid getter
material. The liquid getter material may include a cross-linkable
compound having a thermally reactive group. In this case, the
liquid getter material is cured by a heat treatment.
[0132] It is preferable that the hygroscopic part 38 include at
least one of organometallic compounds, metal oxides and porous
materials such as zeolite, as the liquid getter material. Further,
it is preferable that the component metals of the organometallic
compounds and the metal oxides include at least one of aluminum,
calcium and barium. Organ aluminum compounds, calcium oxide and the
like are more preferred, due to having a high refilling rate of
water.
[0133] The hygroscopic part 38 may include a binder, in particular,
such as at least one of an acrylic resin, an epoxy resins, a
styrene resin, an olefin resin and an amide resin.
[0134] The organic EL element 10B has substantially the same
configuration as that of the organic EL element 10, except that the
organic EL element 10B includes the hygroscopic part 38, which is
mainly different from the configuration of the organic EL element
10. The organic EL element 10B, therefore, achieves at least the
effects similar to those of the organic EL element 10.
[0135] In the organic EL element 10B, a part of the organic EL body
16 exposed from the cathode 18 is covered with the hygroscopic part
38. Consequently, the part of the organic EL body 16 covered with
the cathode 18 allows the cathode 18 to prevent the moisture from
reaching the organic EL body 16, and the part of the organic EL
body 16 exposed from the cathode 18 allows the hygroscopic part 38
to prevent the moisture from reaching the organic EL body 16. As a
result, the moisture hardly reaches the organic EL body 16, so that
deterioration of the organic EL element caused by moisture can be
further prevented, and the life of the organic EL element 10B can
be prolonged.
[0136] Various embodiments of the present invention are described
above. The present invention, however, is not limited to the
various embodiments described above, and various modifications may
be made without departing from the scope of the present
invention.
[0137] The cathode 18 may have a first cathode layer 181 as the
cathode and a second cathode layer 182 functioning as an electron
injection layer described in the first to third embodiments, as in
an organic EL element 10C schematically shown in FIG. 15. Examples
of the material for the second cathode layer 182 include sodium
fluoride (NaF). From the viewpoint of reducing the effect of
moisture invasion into the organic EL element through the second
cathode layer 182, it is preferable that the thickness of the
second cathode layer 182 be thin, ranging, for example, from 1 nm
to 10 nm.
REFERENCE SIGNS LIST
[0138] 10, 10A, 10B, and 10C: ORGANIC EL ELEMENT [0139] 12:
SUPPORTING SUBSTRATE [0140] 12b: SIDE SURFACE (FIRST SIDE SURFACE)
[0141] 12c: SIDE SURFACE (SECOND SIDE SURFACE) [0142] 14: ANODE
(FIRST ELECTRODE) [0143] 16: ORGANIC EL BODY [0144] 16a: EDGE
[0145] 18: CATHODE (SECOND ELECTRODE) [0146] 18a: SIDE SURFACE
[0147] 18b: SIDE SURFACE [0148] 20: SEALING MEMBER [0149] 20a: SIDE
SURFACE [0150] 20b: SIDE SURFACE [0151] 22: EXTRACTING ELECTRODE
[0152] 24: ELECTRODE-ATTACHED SUBSTRATE [0153] 26: REGION FOR
FORMING ORGANIC EL ELEMENT [0154] 36: INSULATING LAYER [0155] 38:
HYGROSCOPIC PART [0156] 141: ANODE BODY (FIRST REGION) [0157] 142:
EXTERNAL CONNECTING PART (SECOND REGION) [0158] 161: LIGHT EMITTING
LAYER.
* * * * *